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1.
首次发表假橐吾属Ligulariopsis Y．L．Chen的核形态研究结果。染色体间期为复杂型,前期染色体为中间型。染色体长度从2．70μm到4．70μm,平均长度为3．62μm,无明显的二型性;核型公式为2n=58=34m+18am(2sat)+6st,核型类型属于2A 。假橐吾属的核型和蟹甲草属与橐吾属相似,但假橐吾属具有较多的亚中部、中部着丝点染色体。 相似文献
2.
本文对蓝钟花属Cyananthus及整个狭义的桔梗科Campanulaceae(s．str.)的花粉、
染色体和形态性状作了深入的系统研究，表明蓝钟花属是该科的最原始类群，它的亲缘属有党
参属Codonopsis和细钟花属Leptocodon。 对蓝钟花属中各个种及它的亲缘属的地理分布分
析，揭示了该属是典型的中国-喜马拉雅区系的成分，横断山地区是该属的频度和多样性中心；
认为中国西南部及其邻近地区至少是桔梗科原始属的保留中心，甚至可能是该科的起源中心。
作者最后对蓝钟花属各个种的性状作了生物统计分析，在此基础上对全属进行了全面的分类
修订，把原有的26个种9个变种归并为19种(包括2亚种)；对该属的次级分类也作了修订。
首次报道了该属的染色体数目和细钟花属的花粉形态。 相似文献
3.
本文着重讨论山豆根属植物的分类、分布、系统亲缘及起源等问题。对本属的分类历史和”山豆
根”一名的由来作了回顾和考证．按中国古典植物文献，”山豆根’指的是Euchresta japonica 。
我们对山豆根属进行一次清理，在本文共报道4种3变种，其中发现一新变种——短管山豆根
Ｅ.tubulosa Dunn var.brevituba C.Chen，井以萼管的有无建立I.山豆根组sect．I．Euchrestae(3种1变
种)及II．管萼组sect．II．Tubulosae(1种2变种)。
山豆根属的现代分布中心在我国中部及南部，可能是第三纪或略早一些的古热带山地森林植物区
系的成员。推测本属可能出现于晚白垩纪，可能是华夏起源。本属的分布区正好处于 “华莱士线”的西
侧，从古地理的资料告诉我们大约在五千万年前，新几内亚和澳大利亚还处在向北移动的状态，这时本
属已遍布东亚和东南亚地区，因此，新几内亚和澳大利亚等地没有本属的分布，这一分布格局正好又一
次证明，在这一地区的诸多的生物地理分界线中，”华莱士线’更符合自然，使我们更清楚的认识到”华莱
士线”的实际意义不仅是劳亚古陆与冈瓦纳古陆的分界线，而且还是亚洲与澳大利亚地区劳亚古陆植物区系与冈瓦纳古陆植物区系的分界线。 相似文献
4.
张明理 《中国科学院研究生院学报》1997,35(2):136-147
锦鸡儿属Caragana是一个典型的温带亚洲分布属。本属在青藏高原和喜马拉雅约有24种1变种，约占整个属的1／3。这些种类几乎全部处于演化高级阶段，且既有叶轴宿存类群，也有假掌状叶类群。反映出种的分化很活跃，在横断山地区形成本属的分布中心、分化中心。本区内绝大多数种类是特有分布。替代现象主要受气候、植被变化作用，沿横断山和喜马拉雅分布的长齿系Ser. Bracteolatae Kom．是一个典型的替代分布类群。锦鸡儿属植物生态适应性很强，可在其生长的灌丛中形成优势种。 寒化和旱化现象十分突出，它们有一系列森林种、草原种和荒漠种及相关的形态变异。用锦鸡儿属植物进行青藏高原和喜马拉雅区域内的分布区关系分析及最小生成树MST和特有性简约性分析(PAE)，表明横断山地区特别是其北部是本属植物的一个地理结点。以此沿横断山向北部唐古特和西部藏东南适应性辐射。横断山和西喜马拉雅联系微弱，看不出植物长距离扩散的踪迹，大多是由于生态因子限制而产生的隔离。虽然本区不可能是锦鸡儿属的起源地，然而，通过本区与邻近地区的地理联系，可推测它们在我国适应性辐射方向是从东北向西南。结合豆科蝶形花亚科其它属化石记录及其分布区局限在温带亚洲等现象，认为锦鸡儿植物是一组特化、晚近衍生的类群，起源于北方东西伯利亚晚第三纪中新世后期至上新世。 相似文献
5.
本文对肋柱花属的属下分类、系统发育和地理分布等方面进行了深入研究。文用分支系统学的方法和原理，用计算机PAUP程序处理，获得了几个最简约的支序图。 肋柱花属属于龙胆亚族辐状花冠群，在这群中，论亲缘关系它与辐花属最近，与獐牙菜属次之，而与黄秦艽属关系较远。 獐牙菜属在进化程度上较肋柱花属低，因此它被选为肋柱花属的外类群。 经过支序分析，肋柱花属的18个种根据Hennig的“共近裔性原则”可组合为三个组，其中肉质根茎组为较原始的组，肋柱花组为中级进化水平的组，合萼组是进化程度最高的组。 肋柱花属是北温带分布型的属，分布于亚洲、欧洲及北美洲，直达北极。从种的地理分布型分析，表明秦岭一横断山区是本属的起源与分化中心。 随文报道了一个新组、一个新种和一个新变种。 研究了全部种类的命名模式。 相似文献
6.
溥发鼎 《中国科学院研究生院学报》1991,29(5):385-393
藁本属Ligusticum L.属伞形科Umbelliferae芹亚科Apioideae Drude阿米芹族Ammineae
Koch。它在阿米芹族中，是一个较进化的类群，是介于阿米芹族与前胡族Peucedaneae DC．之间的一个过渡类型。藁本属全世界60余种。我国现知有34种，占该属种数的二分之一，其中28种及2个栽培变种为我国所特有。本文比较分析藁本属的形态学性状和孢粉学性状，以小总苞片及其相关特征作为该属次级划分的主要依据，将藁本属分为两个类群，并对该属的种类作了增补，对一些种的名称、分布作了补充修订。文中还记载了4个新种。喜马拉雅藁本L．elatum(Edgew.)C.B．Clarke和开展藁本L. thomsonii C. B. Clarke var．evolutior C. B．Clarke，系我国首次记录。 相似文献
7.
马金双 《中国科学院研究生院学报》1989,27(5):321-364
本文通过对东亚和南亚马兜铃属的研究，修改了马兜铃属的分类系统，补充论证了演化趋势；并
在分析该属地理分布的基础上提出马兜铃属分布与分化的第二个中心——中国的横断山区。 本文确
认2亚属、7组、4系、68种和1变种，其中有3新组、2新种及13个新异名。 相似文献
8.
潘锦堂 《中国科学院研究生院学报》1994,32(4):316-327
本文对鬼灯檠属Rodgersia Gray的染色体数、花粉体积和纹饰、萼片数目、萼片脉序和脉型、萼片腹面毛被、花梗和花序轴毛被、叶的类型等关键性状进行了分析，确定了其进化顺序，依据性状的系统发生，绘制了鬼灯檠属的瓦格勒尔系统树；确认本属有5种和3变种，其中以R.podophylla为最原始，R.nepalensis为最进化，而R.aesculifolia，R.sambucifolia．和R.pinnata则居于两者之间。本属分两组Sect．Rodgersia，仅含R．podophylla Sect．Sambucifolia J．T．Pan，含R．aesculifolia，R.sambucifolia，R.pinnata，R.nepalensis。依据种的主要分布区，划本属植物为4个分布类型，即：日本—朝鲜间断分布，秦岭—大巴山分布，横断山分布和东喜马拉雅分布。笔者认为，本属的起源地在日本-朝鲜一带，横断山地区是其现代分布中心和分化中心；本属的散布路线是自日本—朝鲜，经秦岭—大巴山，通过横断山地区而进入东喜马拉雅，本属的起源时间，当在晚第三纪以前(晚白垩世至早第三纪)。此外，还报道了鬼灯檠属植物的花粉形态。 相似文献
9.
记述了菊科6个属的一些新分类群和新分布，包含1个新组、3个新种、3个新变种、1个新名称、1个新组合和5个种的新记录。这些新分类群是黄鹌菜属蓝舌组、振铎黄鹌菜、蓝花黄鹌菜、青海乳苣、黄苞垂头菊、尼泊尔橐吾和半裂橐吾。 相似文献
10.
国产三角瓣花属(茜草科)订正 总被引：1，自引：0，他引：1
阮云珍 《中国科学院研究生院学报》1988,26(6):443-449
三角瓣花属Prismatomeris Thw．在Hooker(1873)和K．Schumann(1891)的茜草
科分类系统中隶于巴戟族Morindeae Miq．但在 Bremekamp(1966年)的分类系统中，其分类
位置未定。本属的胚根下位，花冠裂片镊合状排列和具针晶等特征与巴戟族相同，但它的花
离生，子房2室，胚珠盾形而着生于子房隔膜上半部等特征则与巴戟族明显不同。 因此，
将本属分立作族并置于Bremekamp所定界的茜草亚科Rubioideae中似乎较合适。 本文还提
供了经挑选的本属10对特征及其分类价值的说明。辨别了两个种：(1)将分布于中国的P.
tetrandra(Roxb．)K．Schum. 修订为 “P.tetrandra (Roxb.) K. Schum. subsp. multiflora
(Ridley，)Y．Z．Ruan”. (2)P. connata Y． Z. Ruan 被记述作新种它的热带新亚种是 P. connata Y． Z． Ruan subsp. hainanensis Y． Z． Ruan。 相似文献
11.
傅德志 《中国科学院研究生院学报》1988,26(4):249-264
本文对人字果属Dichocarpum W．T．Wang et Hsiao．的形态、花粉和染色体等性
状，以及地理分布进行了系统研究。确认了该属在毛茛科Ranunculaceae中的地位，并认为可
能与星果草属Asteropyrum Drumm．et Hutch．关系较密切, 证实了该属内存在三沟和散沟两
种花粉类型。该属的染色体基数可能为x=6，产于东亚大陆的种为4倍体，日本的种为6倍
体，原始的2倍体种已灭绝。中国西部山地可能为该属的分布中心，日本的种可能是在第三纪由中国大陆迁移过去的。本文按该属内各种之间可能的亲缘关系，作出了系统排列。 相似文献
12.
本文根据植物类群的系统发育和地理分布统一的原理，讨论了獐牙菜属植物的起源、散布和分
布区的形成。獐牙菜属包括11组16系154种，间断分布在亚洲、欧洲、北美洲和非洲。中国西南部-
喜马拉雅地区汇集了大多数种类、不同演化水平的类群以及形形色色的特有类群，成为该属的多样化
中心和多度中心。该属的原始类群和外类群也集中分布在中国西南山地，极有可能是该属的起源地。该
属的分布区类型中出现了各式的间断分布，根据有该属植物分布的大陆间及大陆与岛屿间分离和连接
的时间推测，该属的起源时间至少不会晚于晚白垩纪，也许更早，可追溯到中白垩纪。通过分类群间亲
缘关系和现代分布分析，显示出该属植物从起源地向周围和一定方向散布，形成了三个主要散布途径。在散布过程中植物本身也发生演化和就地特化，形成新的类群。 相似文献
13.
黄淑美 《中国科学院研究生院学报》1993,31(2):105-126
本文分析溲疏属的重要形态特征的演化趋势，讨论亲缘属的系统位置和地理分布及区系特点，分类系统的修订和补充，并编写了分种检索表。认为雄蕊不定数，花瓣覆瓦状排列，花丝无齿，子房半下位的是属于原始性状，而雄蕊定数，花瓣镊合状排列，花丝具齿，子房下位的是进化性状，因此新溲疏组应包括在溲疏属内，该组与中间溲疏组是原始类群，而溲疏组是进化类群。国产52种被分为2组，4亚组和17系。溲疏属基本上是属于北温带分布类型，而我国的横断山脉至秦岭南部和华中一带为本属的现代分布和分化中心。 相似文献
14.
首次全面论述了全世界黄华属(豆科)植物地理。黄华属是豆科少数几个东亚-北美间断分布属之一。对黄华属5组21种的分布进行了分析,发现本属4个频度分布中心依次是：东亚地区(8种／3组,其中特有种4种),伊朗-土兰地区(7种／3组,其中特有种3种),落基山地区(7种／2组,均为特有种)及大西洋北美地区(3种／1组,均为特有种)。基于以下事实：在东亚地区存在本属最多的组与种;在此区可以见到黄华属系统发育系列;该属最原始的组种及最进化的组种也在该区出现等,可以认为东亚地区是该属的现代分布中心及分化中心。伊朗-土兰地区(中亚东部至喜马拉雅)及落基山地区所含种、组数仅次于东亚地区,而且多倍体现象多发生于这两区,因此可认为是本属的次生分布中心及分化中心。在此二地区,物种分化较活跃且复杂,先后描述了很多新种和变种,也曾进行过较多的归并处理。最近的分子生物学证据不断揭示,在这地区曾被归并的一些分类群存在着较大不同,从而提醒分类学家对年轻区系中物种分化较活跃的类群进行分类处理时,无论是建新分类群还是对某些类群进行归并,应持谨慎态度。作者根据黄华属植物的现代地理分布、形态演化趋势、现有的化石及地质历史资料,推测黄华属植物在中新世之前早已形成,并且在晚第三纪欧亚大陆与北美大陆失去陆地连接之前在两大陆已经存在,很可能是于早第三纪或晚白垩纪在劳亚古陆上起源于一个含羽扇豆生物碱的古槐成员。两大陆分离后,在不同的成种因子的影响下,形成了各自的演化格局：在亚洲,晚第三纪的喜马拉雅造山运动、古地中海消失及第四纪冰川作用引起的旱化、寒化,促进了该属植物的强烈分化;而在北美,第四纪的冰川作用及局部的山体隆起,可能是促进该属植物演化的主要动力。根据黄华属植物的系统演化趋势及原始类群的分布式样分析,东亚地区的中国-日本亚区可能是本属植物的原始类型中心。 相似文献
15.
潘锦堂 《中国科学院研究生院学报》1988,26(2):120-129
In this paper the classification of the genus Bergenia Moench is provided, its
geographic distribution analysed, and the phylogeny also traced. Based on an analysis of
morphological characters such as leaves, ocreas, branches of inflorescences, Pedicels, hypan-
thium, sepals, and glandular indumentum, thi genus is divided into 3 sections: 1. Sect. Scopu-
losae J. T. Pan, sect. nov., 2. Sect. Bergnia, 3. Sect. Ciliatae (A. Boriss.) J. T. Pan, stat. nov.
The Sect. Scopulosae J. T. Pan may be considered as the primitive one, while Sect. Ciliatae
(A. Boriss.) J. T. Pan may be regarded as the advanced one, with Sect. Bergenia in between.
So far, the genus Bergenia Moench comprises 9 species in the total. Southeast Asia and
North Asia (south and east Siberia, USSR) each have only 1 species, West Asia (Afghanis-
tan) has 2, Central Asia (Kirghizia-Tajikistan-Uzbekstan area, USSR) 3, South Asia 4 (Nepal
has 4, India, Pakistan and Kashmir area each has 3, Bhutan and Sikkim each has 2), East
Asia 6. In East Asia, Mongolia and Korea each have only 1 species, but China has 6 (includ-
ing endemic species 2 and new species 1). Sichuan Province and Xizang Autonomous Region
each have 3, Yunnan Province 2, Shaanxi Province (Qinling Mountains) and Uygur Autono-
mous Region of Xinjiang each have only 1.
Thus the distribution centre of this genus should be in the region covering Si-
chuan, Yunnan and Xizang. Moreover, it is noteworthy that Bergenia scopulosa T.
P. Wang in Sect. Scopulosae seems to have retained primitive characters, for exa-
mple, non-ciliate leaves and ocreas, glabrous pedicels, hypanthium and sepals, and
this primitive species is found in Qinling Mountains and Sichuan. According to the
distribution of the primitive species, the author suggests that the centre of origin of
this genus be in the region covering Qinling Mountains and Sichuan. 相似文献
16.
我国悬钩子属植物的研究 总被引：1，自引：0，他引：1
陆玲娣 《中国科学院研究生院学报》1983,21(1):13-25
The genus Rubus is one of the largest genera in the Rosaceae, consisting of more
than 750 species in many parts of the world, of which 194 species have been recorded
in China.
In the present paper the Rubus is understood in its broad sense, including all the
blackberries, dewberries and raspberries, comprising the woody and herbaceous kinds.
So it is botanically a polymorphic, variable and very complicated group of plants.
The detailed analysis and investigation of the evolutionary trends of the main organs
in this genus have indicated the passage from shrubs to herbs in an evolutionary line,
although there is no obvious discontinuity of morphological characters in various taxa.
From a phylogenetic point of view, the Sect. Idaeobatus Focke is the most primitive
group, characterized by its shrub habit armed with sharp prickles, aciculae or setae,
stipules attached to the petioles, flowers hermaphrodite and often in terminal or axill-
ary inflorescences, very rarely solitary, druplets separated from receptacles. Whereas
the herbaceous Sect. Chamaemorus L. is the most advanced group, which is usually
unarmed, rarely with aciculae or setae, stipules free, flowers dieocious, solitary, dru-
plets adhering to the receptacles and with high chromosome numbers (2n = 56).
Basing upon the evolutionary tendency of morphological features, chromosome nu-
mbers of certain species recorded in literature and the distribution patterns of species,
a new systematic arrangement of Chinese Rubus has been suggested by the present
authors. Focke in his well-known monograph divided the species of Rubus into 12
subgenera, while in the Flora of China 8 sections of Focke were adapted, but some im-
portant revisions have been made in some taxa and Sect. Dalibarda Focke has been
reduced to Sect. Cylactis Focke. In addition, the arrangement of sections is presented
in a reverse order to those of Focke’s system. The species of Rubus in China are
classified into 8 sections with 24 subsections (tab. 3) as follows: 1. Sect. Idaeobatus,
emend. Yü et Lu(11 subsect. 83 sp.); 2. Sect. Lampobatus Focke (1 sp.); 3. Sect.
Rubus (1 sp.); 4. Sect. Malachobatus Focke, emend. Yü et Lu (13 subsect. 85 sp.); 5.
Sect. Dalibardastrus (Focke)Yü et Lu (10 sp.); 6. Sect. Chaemaebatus Focke (5 sp.);
7. Sect. Cylactis Focke, emend. Yü et Lu (8 sp.); 8. Sect. Chamaemorus Focke (1 sp.).
In respect to the geographical distribution the genus Rubus occurs throughout the
world as shown in tab. 2, particularly abundant in the Northern Hemisphere, while
the greatest concentration of species appears in North America and E. Asia. Of the
more than 750 species in the world, 470 or more species (64%) distributed in North
America. It is clearly showm that the center of distribution lies in North America at
present time. There are about 200 species recorded in E. Asia, of which the species
in China (194) amount to 97% of the total number. By analysis of the distribution
of species in China the great majority of them inhabit the southern parts of the Yangtze
River where exist the greatest number of species and endemics, especially in south-
western parts of China, namely Yunnan, Sichuan and Guizhou (tab. 3. 4.). It is in-
teresting to note that the centre of distribution of Rubus in China ranges From north-
western Yunnan to south-western Sichuan (tab. 5), where the genus also reaches its
highest morphological diversity.
In this region the characteristics of floristic elements of Rubus can be summarized
as follows: it is very rich in composition, contaning 6 sections and 94 species, about
66% of the total number of Chinese species; there are also various complex groups,
including primitive, intermediate and advanced taxa of phylogenetic importance; the
proportion of endemic plants is rather high, reaching 61 species, up to 44% of the
total endemics in China. It is noteworthy to note that the most primitive Subsect.
Thyrsidaei (Focke) Yü et Lu, consisting of 9 endemic species, distributed in southern
slopes of the Mts. Qin Ling and Taihang Shan (Fig. 4). From the above facts we may
concluded that the south-western part of China is now not only the center of distribu-
tion and differentiation of Rubus in China, but it may also be the center of origin ofthis genus. 相似文献
17.
木兰科分类系统的初步研究 总被引：10，自引：0，他引：10
刘玉壶 《中国科学院研究生院学报》1984,22(2):89-109
A new system of classification of Magnoliaceae proposed. This paper deals mainly with taxonomy and phytogeography of the family Magnoliaceae on the basis of external morphology, wood anatomy and palynology. Different authors have had different ideas about the delimitation of genera of this family, their controversy being carried on through more than one hundred years (Table I). Since I have been engaged
in the work of the Flora Reipublicae Popularis Sinicae, I have accumulated a considerable amount of information and material and have investigated the living plants at their natural localities, which enable me to find out the evolutionary tendencies and primitive morphological characters of various genera of the family. According to the evolutionary tendencies of the characters and the geographical distribution of this family I propose a
new system by dividing it into two subfamilies, Magnolioideae and Liriodendroideae Law (1979), two tribes, Magnolieae and Michelieae Law, four subtribes, Manglietiinae Law, Magnoliinae, Elmerrilliinae Law and Micheliinae, and fifteen genera (Fig. 1 ), a system which is different from those by J. D. Dandy (1964-1974) and the other authors.
The recent distribution and possible survival centre of Magnoliaceae. The members of Magnoliaceae are distributed chiefly in temperate and tropical zones of the Northern Hemisphere, ——Southeast Asia and southeast North America, but a few genera and species also occur in the Malay Archipelago and Brazil of the Southern Hemisphere. Forty species of 4 genera occur in America, among which one genus (Dugendiodendron) is endemic to the continent, while about 200 species of 14 genera occur in Southeast Asia, of which 12 genera are endemic. In China there are about 110 species of 11 genera which mostly occur in Guangxi, Guangdong and Yunnan; 58 species and more than 9 genera occur in the mountainous districts of Yunnan. Moreover, one genus
(Manglietiastrum Law, 1979) and 19 species are endemic to this region. The family in discussion is much limited to or interruptedly distributed in the mountainous regions of Guangxi, Guangdong and Yunnan. The regions are found to have a great abundance of species, and the members of the relatively primitive taxa are also much more there than in the other regions of the world.
The major genera, Manglietia, Magnolia and Michelia, possess 160 out of a total of 240 species in the whole family. Talauma has 40 species, while the other eleven genera each contain only 2 to 7 species, even with one monotypic genus. These three major genera are sufficient for indicating the evolutionary tendency and geographical distribution of Magnoliaceae. It is worthwhile discussing their morphological characters and
distributional patterns as follows:
The members of Manglietia are all evergreen trees, with flowers terminal, anthers dehiscing introrsely, filaments very short and flat, ovules 4 or more per carpel. This is considered as the most primitive genus in subtribe Manglietiinae. Eighteen out of a total of 35 species of the genus are distributed in the western, southwest to southeast Yunnan. Very primitive species, such as Manglietia hookeri, M. insignis and M. mega-
phylla, M. grandis, also occur in this region. They are distributed from Yunnan eastwards to Zhejiang and Fujian through central China, south China, with only one species (Manglietia microtricha) of the genus westwards to Xizang. There are several species distributing southwards from northeast India to the Malay Archipelago (Fig. 7).
The members of Magnolia are evergreen and deciduous trees or shrubs, with flowers terminal, anthers dehiscing introrsely or laterally, ovules 2 per carpel, stipule adnate to the petiole. The genus Magnolia is the most primitive in the subtribe Magnoliinae and is the largest genus of the family Magnoliaceae. Its deciduous species are distributed from Yunnan north-eastwards to Korea and Japan (Kurile N. 46’) through Central
China, North China and westwards to Burma, the eastern Himalayas and northeast
India. The evergreen species are distributed from northeast Yunnan (China) to the
Malay Archipelago. In China there are 23 species, of which 15 seem to be very primi-
tive, e.g. Magnolia henryi, M. delavayi, M. officinalis and M. rostrata, which occur in
Guangxi, Guangdong and Yunnan.
The members of Michelia are evergreen trees or shrubs, with flowers axillary, an-
thers dehiscing laterally or sublaterally, gynoecium stipitate, carpels numerous or few.
Michelia is considered to be the most primitive in the subtribe Micheliinae, and is to
the second largest genus of the family. About 23 out of a total of 50 species of this
genus are very primitive, e.g. Michelia sphaerantha, M. lacei, M. champaca, and M.
flavidiflora, which occur in Guangdong, Guangxi and Yunnan (the distributional center
of the family under discussion) and extend eastwards to Taiwan of China, southern
Japan through central China, southwards to the Malay Archipelago through Indo-China.
westwards to Xizang of China, and south-westwards to India and Sri Lanka (Fig. 7).
The members of Magnoliaceae are concentrated in Guangxi, Guangdong and Yunnan
and radiate from there. The farther away from the centre, the less members we are
able to find, but the more advanced they are in morphology. In this old geographical
centre there are more primitive species, more endemics and more monotypic genera.
Thus it is reasonable to assume that the region of Guangxi, Guangdong and Yunnan,
China, is not only the centre of recent distribution, but also the chief survival centreof Magnoliaceae in the world. 相似文献
18.
中国柳属植物地理分布的研究 总被引：2，自引：0，他引：2
赵士洞 《中国科学院研究生院学报》1987,25(2):114-124
本文研究了中国产柳属植物的分布，并探讨了该属的起源与演化问题。 我国产柳
属植物255种，约占全世界总数的46％，隶属于37个组，几乎包括了该属所有的进化类型。
因此，中国是世界柳属植物种数最多、类型最丰富的地区。青藏高原的出现，是形成这一分布
特点的重要原因。我国柳属植物主要分布在西北、东北和西南地区。西北地区是中亚分布区
的一部分; 东北地区是东北亚分布区的一部分; 它们又都有一些中欧-西伯利亚和北极-高山成
分。青藏高原与其他分布区间的联系很少，是柳属又一个重要的分布中心。作为泛北极植物
区系的典型属之一的柳属，可能起源于东南亚热带山区。 相似文献
19.
重楼属Paris有19种，分布于欧亚大陆。根据对本属所有种的染色体研究，重楼属染色体基数为5，核型的基本结构有两种形式：热带核型K2n＝2x=10=6m十4t和温带核型K2n=2x=10＝6m+4st或 6m+2st十2t。 热带核型的种(13种)分布在亚洲大陆的热带和亚热带；温带核型的种(6种)则出现在欧亚大陆的温带地域。重楼属的多倍体种的核型属温带核型，为本属的边陲种。四倍体种四叶重楼Paris quadrifolia分布在本属分布区的西端(欧洲)；日本重楼P.japonica是八倍体种，局限在属分布区的东端(日本)。全部热带核型的种都是二倍体种。其中海南重楼P.dunniana等较原始种类都集中在华南和中南半岛北部。作者认为，亚洲大陆北纬18°至北回归线的热带地域是重楼属的起源地，云贵高原至邛崃山地域拥有14种重楼和9种核型结构式(全属有13种核型结构式)，是重楼属的多样化中心，即现代分布中心。 相似文献
20.
中国-喜玛拉雅特有属——蓝钟花属的分类修订 总被引：2，自引：0，他引：2
Krishna K. Shrestha 《中国科学院研究生院学报》1997,35(5):396-433
Cyananthus Wallich ex Bentham, the only genus of Campanulaceae with superior ovary, is revised to clarify infrageneric relationships and phylogeny of the genus. Evidence obtained from the comparative gross morphology, anatomy, palynology, and karyomorphology recommends a new infrageneric classification of the genus, recognizing 23 species, belonging to two subgenera, four sections and four subsections. One subgenus(Subgen. Micranthus), one section(Sect. Suffruticulosi) and two subsections(Subsect. Flavi and Subsect. Lichiangenses)are described as new taxa. New combinations at sectional(Sect. Annui) and subsectional(Subsect. Stenolobi) ranks are also proposed. The genus Cyananthus is strictly distributed in the high mountains of China(Xizang, Yunnan and Sichuan), extending to Bhutan, Nepal and India(Kumaon-Garhwal, Assam and Sikkim), with altitudinal ranges from 2500～5300 m. It is observed that 13 species are endemic to SW China and only three species are endemic to the Himalayas(two species in Nepal and one to NW India). It is evident that Cyananthus is one of the most primitive genera of Campanulaceae and within the genus, subgenus Cyananthus(Sect. Stenolobi) is more primitive than the subgenus Micranthus. It is also suggested that SW China(most probably Yunnan) is the center of origin of Cyananthus, considering the occurrence of as many as 20 species of Cyananthus, representing several primitive taxa and many endemic species. 相似文献